In the present investigation, GO was prepared by exfoliation of graphite using modified Hummer's method and then reduced using hydrazine hydrate (reducing agent) to produce rGO. XRD, FESEM, Raman, FTIR spectrophotometer and TGA were used for characterization of GO and rGO. XRD images reveal crystalline structure for both GO and rGO. The d‐spacing is observed to be reduced for rGO as compared to that for GO because of removal of oxygen containing functional groups. Raman excitation peaks were obtained for two laser wavelengths 532 and 785 nm. Ratio of intensities of D and G bands (ID/IG) increase for rGO due to increase in order by reduction, implying restoration of the p‐conjugation. The bands are narrower for rGO.TGA thermograms show a higher overall loss of weight for GO in the temperature range 0–1000 °C under N2 flow. Intensity of FTIR peaks of oxide, hydroxyl and alkoxy groups decreases significantly on reduction. FESEM image shows more corrugated surface of rGO as compared to GO. It is expected that this investigation would be useful to develop GO/rGO based gas sensors to detect minute concentration of gases.

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A SnOx/Au/SnOx transparent conductive oxide (TCO) multilayered film was fabricated with a total thickness of 75 nm using both e-beam and thermal evaporation techniques.

In the present report, gas sensing devices based on LaFeO 3 and rGO-LaFeO 3 were fabricated by a photolithography technique. The X-ray diffraction, Raman spectra and FT-IR results confirm the formation of a perovskite phase and composite. XPS and TEM give the chemical compositions for both products. The higher roughness, greater surface area (62.1 m 2 g À1 ), larger pore size (16.4 nm) and lower band gap (1.94 eV) of rGO-LaFeO 3 make it a suitable candidate to obtain high sensitivity. The gas sensing performance of the devices was investigated for various concentrations of NO 2 and CO gases at temperatures of 200 and 250 C. It was observed that the rGO-LaFeO 3 based device exhibited a high relative response (183.4%) for a 3 ppm concentration of NO 2 at a 250 C operating temperature. This higher response is attributed to the large surface area, greater surface roughness, and numerous active sites of rGO-LaFeO 3 . The gas sensing properties investigated show that rGO-LaFeO 3 is an excellent candidate for an NO 2 sensor.